Analyzing Cannabis and Infused Foods … State by State by State

With the advent of state—but not federal—legalized consumption of marijuana, the diversity of delivery systems and forms of consumption can be astonishing. It can be smoked or “vaped,” it can be a cream, ointment or ingredient in foods and drinks. This creates some unique challenges for organizations associated with laboratory quality control and safety testing. Laboratories, reference material producers, proficiency testing providers, and standards developers encounter unique cannabis-specific issues, both legal and technical that do not exist for other goods and, at present, cannot be easily addressed or taken for granted.
 

“Normal” testing.

For most products, laboratory quality control and safety testing follows a fairly straightforward approach: The lab confirms that it has the appropriate facilities, testing and measurement equipment, and staff to perform the analysis. Up to this point, the cannabis lab community is generally indistinguishable from any other. But the path soon diverges. Because cannabis remains illegal under federal law, each of the 20-plus states that permit medical- or recreational-use cannabis has its own set of regulations—as varied as the states themselves.

As is true for the analysis of any product, a laboratory needs to ensure that the method of analysis has been validated as being capable of detecting and quantifying the analytes of interest and in the expected matrices. To ensure the results will be valid, the lab must consider how it will achieve traceability of the measurement. This is typically obtained through the use of external reference source(s).

The laboratory generally also attempts to participate in relevant proficiency testing; then it needs a sample for testing that is representative of the whole. Finally, control of the testing process should be governed by an applicable quality management system.

While these means of assurance are generally readily available for normal analytical testing regimens, cannabis is not a “normal” product.
 

The Cannabis Challenge.

Accordingly there are several challenges currently faced by the cannabis-testing community:

• Reference materials. While the availability of appropriate, Guide 34-accredited reference chemicals appears to be catching up with the needs of the industry, not all cannabinoids of interest are commercially available, and those that are may be of variable purity. Also, since cannabinoids are Schedule I controlled substances, DEA limits shipments to concentrations below 1,000 ppm. This may limit their usefulness as reference standards and laboratory controls. In contrast, for the most part, representative accredited microbial reference materials are available.
• Methods. Fairly well-established analytical methods for analyzing cannabis and cannabis-infused products for potency, cannabinoid profile, terpenes, and contaminants are generally available. However, many of these were not developed specifically for cannabis or for the many, relatively lesser-researched matrices; nor have they typically undergone the multi-site validations, due to the federal strictures in their shipment. As a result, often each lab must undertake the validation process themselves, which may limit the sharing of methods between laboratories.
• Proficiency testing programs. To demonstrate accuracy and comparability among laboratories, the use of matrix-matched, blind samples of materials likely to be encountered help provide confidence in the laboratory’s competence. However, commercial shipping restrictions limit the type of sample-sharing seen even in self-organized, inter-laboratory comparison programs. So it is unsurprising that, to date, there have been no commercial proficiency testing provider organizations (accredited or unaccredited) with realistic cannabis-sample analysis comparison programs.
• Sampling and sample sizes. Unlike “normal” laboratories a cannabis-testing laboratory does not typically receive commensurately sized quantities of test materials Also due to the heterogeneity of the plant itself, a small sample can be problematic if it is not statistically representative of the batch. The sampling plan must account the needed confidence that a given sample size and collection approach will be both representative and statistically adequate to identify the analyte of interest.
• Quality management systems. There is, at present, no consistent approach among states for the recognition of laboratory competence. Some states have no requirements; some control the certification process; some use a combination of ISO/IEC 17025 accreditation and state certification; others use NELAC environmental laboratory accreditation programs. Additionally some recognition schemes advocate use of Good Laboratory or Manufacturing Practices (GLPs and GMPs).
  
   

Who should test it?

Related to this is the question of who should do the testing (i.e., first-, second-, or third-party, private, or public sector laboratories). Currently there is no consistency. In regulatory third-party programs, the cannabis-testing labs determine if the products or production processes conform to standards and characteristics of quality. Most often these are established by the responsible governmental agency (in this case, the state). In other regulatory programs, agencies have required compliance with privately established “voluntary consensus standards.” However, more and more states are beginning to rely on ISO 17025.

All in all, these varied approaches and challenges are likely a reflection of the newness of state regulation of cannabis. As federal agencies become involved in legalization efforts, the laboratory testing infrastructure will likely come increasingly closer to the norm of what is seen in other, more-established industries that are less constrained by the legal status of the materials under analysis.